The civilization was advanced, having had space flight for several hundred years, but it had elected not to venture outside of its star system.

Eminiar VII had been fighting a war with Vendikar, its colony on the third planet in the system, for five hundred years. The conditions of this war were stipulated in a treaty signed by both worlds. This was a simulated war with causalities determined by computer projections, and the people willingly killing themselves in disintegration stations. Every year, on Eminiar, one to three million were killed by this process. Legitimate targets in the war included vessels orbiting the planet, a fact that caused Kirk considerable difficulty during his visit. The reneging of this treaty by either side could result in a real war.

In 2217, the USS Valiant visited this planet. During its visit, the star cruiser and its crew were declared causalities of this war. The Eminians successfully destroyed the ship and killed its crew.

In 2267, the USS Enterprise visited this planet on a mission to open diplomatic relations with Eminiar VII. During the visit, when his ship and crew were threatened with the same fate as the Valiant, CaptainJames T. Kirk ended the war abruptly by destroying the computers that were conducting the simulated war. AmbassadorRobert Fox began work with the two planets to create a lasting peace and to establishment of a Federation treaty port. (TOS: "A Taste of Armageddon")